Mercedes techs checked the computer codes that indicated a problem with crankshaft positioning. They also indicated that it apppeared this was caused during operation at higher elevations which makes sense since each time the check engine light went off it was while operation in the North Carolina Appalachian mountains around 3,700 feet above sea level.

Well, the bottom line is several issues can cause this to happen and I guess it is trial and error from here. They indicated that it could be the crankshaft positioning sensor which is a 3 hour labor job to try trial and error fixes. I hate to authorize repairs if this ends up not being the problem and we have to go on from here. This could end up being expensive if we do a try this and try that approach. Anyway, for now I guess the car will be fine if we do not drive it at higher elevations.